Ink-jet apparatuses in which image formation is effected by discharging a functional material such as ink onto a recording medium by using an ink-jet head has characteristics such as that they are environmentally friendly, that high-speed recording is possible on various recording media, and that bleeding is unlikely to occur and high-resolution images can be obtained. Further, if a full-line head system in which heads are arrayed over the entire recording width is used, an even higher speed is possible, and development is underway which combines the full-line head system and an ultraviolet-curable ink for which a drying process is not required in many cases.
Meanwhile, in such an ink-jet recording apparatus, the ink-jet head has a multiplicity of nozzles, and if faulty discharge from the nozzles occurs, it is visibly recognized as an image defect. For this reason, pressurization, suction purge, and preliminary discharge of the ink are generally carried out at timings at which the head moves to the position of a maintenance station for each time period. However, in the recording apparatus in which a web-like recording medium is fed, the head is generally fixed to the apparatus, and the recording medium is constantly present below the head, so that ink refresh operation cannot be performed. When maintenance is actually provided, either the head or a recording material transporting device is moved to execute the maintenance of the head. However, at this juncture, a reference position must be reset, so that there has been a high probability of occurrence of a faulty recording image due to positional offset.
In view of such a background, ink-jet recording methods have been disclosed in which preliminary maintenance discharge is carried out for suppressing the occurrence of faulty nozzle discharge (e.g., refer to JP-A-55-139269 and JP-A-2006-76247 (corresponding to US2006/0055715A1)).